Jeff Shelton, IGS, takes a closer look at the current state of air cannon maintenance within the cement industry, detailing why these practices need to be adapted in order to get the most out of what air cannons have to offer.
If the cement industry has revealed anything about air cannons, it is that frequent cannon maintenance is critical for cleaning build-up. The best and most efficient air cannons in the world still have to be worked on from time to time. Back in the 1970s, when air cannons were first introduced to the cement industry, this technology provided a service that was otherwise unavailable. However, air cannons required frequent maintenance in order to continue working properly.
Back in those days, the industry accepted the inconvenience of maintenance and took proper steps to accommodate it because of the operational benefits obtained from their enhanced cleaning capabilities. Air cannons and their technological advancements became widely accepted in the industry. Air cannon flaws were also accepted, or at least tolerated. These flaws included cleaning only 1 m in front of the air cannons and being located in inaccessible areas.
Safety requirements have since changed, making it much harder to work on air cannons. In some plants, maintenance on air cannons is no longer allowed while the plant is in operation. Plants have also reduced their workforce so that they no longer have the people to perform maintenance. This has become an industry-wide problem.
Air cannon technology is largely the same as it was in the 1970s. One can point out that some of the designs have become more maintenance friendly. Yet, while air cannon design has changed little, the cleaning requirements have become more difficult. First, the cleaning area for air cannons has become larger as plant size has increased. In the 1970s, a cleaning distance of 1 m was enough, but this is no longer the case. The change in fuels has also made build-up more difficult to clean. This increased build-up, which requires more cleaning energy, has created a more demanding task for the air cannons of today. Combine this with the new safety requirements, and the benefits obtained from air cannon cleaning has been greatly reduced. It is now the time to no longer accept the air cannon performance from the 1970s and demand more.
The demands on air cannons have only increased over time. This, however, does not mean they are incapable of keeping up with these new demands. Maintenance requirements remain high and will continue to do so unless plants start protecting their air cannons from the harsh cement production environment. Most air cannon OEMs recommend that installation of the air cannon should be as close to the discharge as possible to maximise efficiency. This places the air cannon in the position where it must deal with the harsh environment of the cement process. This includes high levels of heat and material from the process entering the valve assembly. No air cannon in the world can handle this harsh working environment. For the air cannon to be reliable, one must either move the air cannon away from the process, or protect it. Protecting the air cannon is essential for good operation, but protection does not mean all maintenance is eliminated – it can be greatly reduced, but not eliminated altogether. It is also essential that air cannons are installed in a manner that protects the maintenance crews. If an air cannon is worth purchasing, it is worth it to install the cannon in a way that maintenance work can be performed safely.
Enjoy what you've read so far? To read the rest of this article and access the entire October issue of World Cement, click here to register for free!
Read the article online at: https://www.worldcement.com/special-reports/12102022/having-a-blast/
You might also like
Christian Pfeiffer has been assigned with the delivery of a complete grinding circuit, consisting of a Ø5.0 x 16.25m ball mill and an QDK T 250-Z high efficiency separator, completed by auxiliary equipment and conveying systems.